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1.
Molecules ; 27(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36432206

RESUMO

There is an increasingly urgent call to shift industrial processes from fossil fuel feedstock to sustainable bio-based resources. This change becomes of high importance considering new budget requirements for a carbon-neutral economy. Such a transformation can be driven by traditionally used plants that are able to produce large amounts of valuable biologically relevant secondary metabolites. Tobacco plants can play a leading role in providing value-added products in remote areas of the world. In this study, we propose a non-exhaustive list of compounds with potential economic interest that can be sourced from the tobacco plant. In order to optimize extraction methodologies, we first analyzed their physico-chemical properties using rapid solubility tests and high-resolution microfractionation techniques. Next, to identify an optimal extraction for a selected list of compounds, we compared 13 different extraction method-solvent combinations. We proceeded with profiling some of these compounds in a total of six varieties from Nicotiana tabacum and Nicotiana rustica species, identifying the optimal variety for each. The estimated expected yields for each of these compounds demonstrate that tobacco plants can be a superior source of valuable compounds with diverse applications beyond nicotine. Among the most interesting results, we found high variability of anatabine content between species and varieties, ranging from 287 to 1699 µg/g. In addition, we found that CGA (1305 µg/g) and rutin (7910 µg/g) content are orders of magnitude lower in the Burley variety as compared to all others.


Assuntos
Fracionamento Químico , Nicotiana , Nicotiana/química , Nicotina/metabolismo
2.
Front Neurol ; 12: 791608, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069421

RESUMO

Drug-resistant epilepsy remains a significant clinical and societal burden, with one third of people with epilepsy continuing to experience seizures despite the availability of around 30 anti-seizure drugs (ASDs). Further, ASDs often have substantial adverse effects, including impacts on learning and memory. Therefore, it is important to develop new ASDs, which may be more potent or better tolerated. Here, we report the preliminary preclinical evaluation of BICS01, a synthetic product based on a natural compound, as a potential ASD. To model seizure-like activity in vitro, we prepared hippocampal slices from adult male Sprague Dawley rats, and elicited epileptiform bursting using high extracellular potassium. BICS01 (200 µM) rapidly and reversibly reduced the frequency of epileptiform bursting but did not change broad measures of network excitability or affect short-term synaptic facilitation. BICS01 was well tolerated following systemic injection at up to 1,000 mg/kg. However, we did not observe any protective effect of systemic BICS01 injection against acute seizures evoked by pentylenetetrazol. These results indicate that BICS01 is able to acutely reduce epileptiform activity in hippocampal networks. Further preclinical development studies to enhance pharmacokinetics and accumulation in the brain, as well as studies to understand the mechanism of action, are now required.

3.
ACS Omega ; 3(6): 6206-6216, 2018 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458803

RESUMO

A series of zirconium-based catalysts were prepared for the selective transfer hydrogenation of biomass-derived furfural (FFR) into furfuryl alcohol with lower alcohols as hydrogen sources. The sample structures were clearly characterized using various methods, such as X-ray powder diffraction, thermogravimetric analysis, scanning electron microscope, NH3-temperature-programmed desorption (TPD), CO2-TPD, and nitrogen physisorption. Excellent furfuryl alcohol yield of 98.9 mol % was achieved over Zr(OH)4 using 2-propanol as a hydrogen donor at 447 K. The poisoning experiments indicated that basic centers displayed pronounced effect for FFR transfer hydrogenation. Moderate monoclinic phase content in ZrO2-x enhanced the conversion rate and furfuryl alcohol selectivity, whereas acid-basic site density ratio had slight influence on FFR conversion. Besides, Zr(OH)4 revealed good performance and stability after being repeated four times. The possible mechanism for this transfer hydrogenation process over Zr(OH)4 catalyst with 2-propanol as the hydrogen source was proposed.

4.
Nat Prod Commun ; 10(4): 597-603, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25973486

RESUMO

Inflammation plays a major role in many diseases, for instance in arteriosclerosis, rheumatoid arthritis, autoimmune disorders and cancer. Since many plants contain compounds with anti-inflammatory activity, their consumption may be able to prevent the development of inflammatory-based diseases. Edible ferns are some of the most important wild vegetables in China and have traditionally been used both for dietary and therapeutic purposes. In this study we investigated the anti-inflammatory and antioxidant potential of fern extracts from Matteuccia struthiopteris, Osmundajaponica, Matteuccia orientalis and Pteridium aquilinum intended for use as nutraceuticals. Two modes of action were investigated: the inhibition of the pro-inflammatory gene expression of interleukin-1 beta (IL1-ß) and interleukin-6 (IL6), and the gene expression of iNOS by LPS-elicited macrophages. The results showed a decrease of IL1-ß gene expression for the five fern extracts. This effect was more pronounced for the extracts prepared from the roots of O. japonica (IC50 of 17.8 µg/mL) and the young fronds of M orientalis (50.0 µg/mL). Regarding the indirect measurement of NO, via iNOS gene expression, an interesting decrease of 50% was obtained with the extract of M. orientalis fronds at a low concentration (20 µg/mL) compared with P. aquilinum fronds (160 µg/mL) and leaves of O. japonica. The latter showed a higher decrease but at a high concentration of extract (160 µg/mL). The five fern extracts were also evaluated for their ability to scavenge 2,2-diphenyl-l-picrylhydrazyl (DPPH) radicals and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS). All fern extracts exhibited antioxidant effects but the roots of O. japonica and the fronds of M orientalis were most efficient. The HPLC-MS analysis of the constituents of the fern extracts confirmed the presence of chlorogenic acid, caffeic acid, p-coumaric acid, ferulic acid, kaempferol and apigenin, molecules known to exhibit antiinflammatory and/or antioxidant properties.


Assuntos
Anti-Inflamatórios/química , Antioxidantes/farmacologia , Suplementos Nutricionais , Gleiquênias/química , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Linhagem Celular , China , Dronabinol/análogos & derivados , Indanos/química , Macrófagos/efeitos dos fármacos , Camundongos , Estrutura Molecular , Sesquiterpenos/química
5.
Zhongguo Zhong Yao Za Zhi ; 35(16): 2099-102, 2010 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-21046738

RESUMO

Based on the approaches of TLC identification, HPLC for assaying managiferin, and of the determination of water, total ash and acid-insoluble ash in 12 samples, collected from southwest of China, the quality standard of Gentiana rhodantha has been established. The results show the reference materia medica and mangiferin can be both well used as reference substances for TLC identification; the mass fractions of mangiferin is 0.7%-4.4% (average 2.8%), water 6.1%-8.6% (average 7.2%), total ash 3.7%-10.8% (average 6.6%) and acid-insoluble ash 0.2%-2.7% (average 1.3%). The recommended standards of quantitative indexes are that the mass fractions of mangiferin is not less than 2.0%, and the water, total ash and acid-insoluble ash are not more than 9.0%, 8.0% and 3.0% respectively.


Assuntos
Medicamentos de Ervas Chinesas/análise , Gentiana/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Reprodutibilidade dos Testes
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